Show simple item record

dc.contributor.authorJodwalis, Clara Mary
dc.date.accessioned2018-08-08T19:03:21Z
dc.date.available2018-08-08T19:03:21Z
dc.date.issued1998
dc.identifier.urihttp://hdl.handle.net/11122/9483
dc.descriptionThesis (Ph.D.) University of Alaska Fairbanks, 1998
dc.description.abstractSulfur gases and aerosols are important in the atmosphere because they play major roles in acid rain, arctic haze, air pollution, and climate. Globally, man-made and natural sulfur emissions are comparable in magnitude. The major natural source is dimethyl sulfide (DMS) from the oceans, where it originates from the degradation of dimethysulfonioproprionate (DMSP), a compound produced by marine phytoplankton. Global budgets of natural sulfur emissions are uncertain because of (1) the uncertainty in the traditional method used to estimate DMS sea-to-air flux, and (2) the spatial and temporal variability of DMS sea-to-air flux. We have worked to lessen the uncertainty on both fronts. The commonly used method for estimating DMS sea-to-air flux is certain to a factor of two, at best. We used a novel instrumental technique to measure, for the first time, sulfur gas concentration fluctuations in the marine boundary layer. The measured concentration fluctuations were then used with two established micrometeorological techniques to estimate sea-to-air flux of sulfur. Both methods appear to be more accurate than the commonly used one. The analytical instrument we used in our studies shows potential as a direct flux measurement device. High primary productivity in high-latitude oceans suggests a potentially large DMS source from northern oceans. To begin to investigate this hypothesis, we have measured DMS in the air over northern oceans around Alaska. For integrating and extrapolating field measurements over larger areas and longer time periods, we have developed a model of DMS ocean mixing, biological production, and sea-to-air flux of DMS. The model's main utility is in gaining intuition on which parameters are most important to DMS sea-to-air flux. This information, along with a direct flux measurement capability, are crucial steps toward the long-term goal of remotely sensing DMS flux. A remote sensing approach will mitigate the problems of spatial and temporal variability. The new developments in methodology, field sampling, and modeling put forth in this thesis are tools we have used to better understand and quantify sulfur gas emissions from northern oceans, which appear to be a significant source of sulfur to the global atmosphere.
dc.subjectAnalytical chemistry
dc.subjectRemote sensing
dc.subjectPhysical oceanography
dc.titleOceanic emissions of sulfur: Application of new techniques
dc.typeThesis
dc.type.degreephd
dc.identifier.departmentDepartment of Chemistry and Biochemistry
dc.contributor.chairBenner, Richard L.
refterms.dateFOA2020-03-06T01:24:30Z


Files in this item

Thumbnail
Name:
Jodwalis_C_1998.pdf
Size:
3.930Mb
Format:
PDF

This item appears in the following Collection(s)

Show simple item record